Prevalence, antibiotic resistance pattern for bacteriuria from patients with urinary tract infections

Abstract Background and Aims Antibiotic resistance presents a significant global public health challenge, particularly for urinary tract infections (UTIs), and is notably severe in developing countries. Surveillance of the antimicrobial susceptibility patterns of UTI‐causing bacteria is crucial for effective treatment selection. This study aimed to analyze these patterns in bacteria isolated from the urine samples of patients at Mughda Medical College Hospital, Dhaka, Bangladesh. Methods A retrospective study (January 2019 to December 2020) at Mugdha Medical College and Hospital, Dhaka, examined clinical and laboratory data from patients with positive urine cultures (≥105 CFU/mL). The study classified patients into four age groups: children (1–<18 years), young adults (18–<33 years), middle‐aged adults (33–50 years), and old adults (>50 years). The standard Kirby‐Bauer method was used to assess antibiotic sensitivity to 28 common antibiotics. Results Among 243 positive urine cultures in both community‐ and hospital‐acquired UTIs, Escherichia coli was the most common uropathogen (65.84%), followed by Klebsiella spp. (12.34%), Enterococcus spp. (8.23%), and other types of bacteria. Conclusion Old adults are particularly vulnerable to UTIs, with E. coli being the predominant causative agent in the study region. The observed antimicrobial resistance patterns underscore the necessity of judicious antibiotic selection to effectively treat UTIs across different age groups.


| INTRODUCTION
4][15] A previous study showed that sexually active women are more susceptible to UTIs than men. 16One in five women may have a UTI at some point in their life.Repeated UTIs are more likely to occur if someone has already experienced UTIs.8][19] Owing to less concern regarding hygiene, old adults (>65 years) had the highest incidence, followed by young adults. 20Therefore, UTIs complicate the daily lives of people of all ages, notably middle-aged adult women and the oldadult population.
Pain or burning during urination, frequent urination, bloody urine, feeling the need to urinate despite having an empty bladder, and pressure or cramping in the groin or lower abdomen are some of the consequences of UTI.Therefore, these symptoms complicate the livelihoods of the affected individuals, and the treatment of UTIs is urgent.Antibiotics are commonly used to treat UTIs, because they are often caused by bacterial agents.2][23][24] Taking antimicrobial drugs only by observing the symptoms of UTIs rather than by proper laboratory diagnosis is one of the main reasons for the evolution of resistant organisms.Selfmedication and overuse of antimicrobial drugs are practiced by many people in Bangladesh [18-20].6][27][28] The long-term use of antimicrobials can eradicate the growth of normal urethral flora, thus maximizing the growth of pathogenic bacteria. 26,28,29Antimicrobial resistance of microbes is a rigorously evolving phenomenon.It is crucial to maintain a continuous surveillance regime to monitor susceptibility patterns to different commonly used antibiotics.
Developmental nations such as Bangladesh do not adhere to the World Health Organization's recommendations in this regard, whereas developed nations do.
In a previous study, 920 (29%) of 4500 samples from Bangladesh were UTI-positive. 6,30In another study, prevalence was highest in the summer. 31,32In more than 60% of cases, microorganisms exhibit resistance to commonly used antibiotics, such as Cefixime, Ciprofloxacin, Amoxicillin, Nalidixic acid, and Cephalosporins. 33These facts raise ineligibility difficulties associated with UTI treatment.Detailed profiling of individual pathogens is necessary.The study population comprised a wide range of ages (1-95), which were divided into different age groups, thus providing a thorough proportional understanding of vulnerability patterns of UTI infection in different age groups. 34In addition, only reports of infected individuals were collected deliberately, which ensured a focused antibiotic susceptibility analysis with minimal bias.
This study aimed to investigate the recent status of prevalence of bacteriuria infection and its antimicrobial susceptibility patterns among UTI-positive patients at Mugdha Medical College Hospital.This will also help to understand the antimicrobial resistance pattern and choose appropriate antibiotics to treat UTI.

| Study design and population
This retrospective study was conducted at the Mugdha Medical College and Hospital in Dhaka, spanning a period of 2 years from January 2019 to December 2020.This study aimed to analyze the clinical and laboratory findings of individuals exhibiting positive urine cultures with a bacterial count of 10 5 colony-forming units per mL (CFU/mL) of urine.The patient cohort was stratified into four distinct age groups: children and adolescents (1-<18 years), young adults (18-<33 years), middle-aged adults (33-50 years), and old adults (>50 years).Subsequently, an antibiotic sensitivity assay was conducted using the widely recognized Kirby-Bauer method to assess the susceptibility of the isolated bacteria to the 28 most frequently prescribed antibiotics.

| Data collection tools
Data were collected from laboratory reports that contained information about uropathogenic bacterial isolates, bacterial sensitivity, and antibiotic resistance.

| Data collection
This was a retrospective study conducted by collecting information from medical files, such as the date of sample collection, sex and age of patients, bacterial isolates, antibiotics prescribed, and concomitant diseases.

| Statistical analysis
Data were entered into a database designed using a Google Sheet and analyzed using MS Excel (version 2013) software.Retrospective study statistics showed the percentage of uropathogens and antibiotic resistance/sensitivity over a particular period.The overall 2-years resistance/sensitivity rates of the most common uropathogens to routinely tested first-line antimicrobials were calculated by dividing the number of urinary isolates that were resistant or sensitive to each antimicrobial agent by the number of isolates tested against an individual antimicrobial agent.Tables are presented as frequencies (counts) and percentages.

| Distribution of UTI among gender and age groups of the patients
A total of 243 UTI-positive samples were selected for this study, which consisted of 200 (82%) female and 43 (18%) male patients, indicating that the prevalence of UTI in female patients was much higher than that in male patients.Patients were divided into four age groups to track the distribution of uropathogens according to age.

| Distribution of uropathogens among different gender and age groups
Furthermore, we analyzed the distribution of uropathogenic bacteria among different sexes and age groups.The prevalence of Streptococcus spp., E. coli, Enterococcus spp., Staphylococcus spp., and Klebsiella spp. was higher in females than in males.In contrast, the prevalence of Proteus spp. was higher in male patients compared to in women.A similar prevalence of Pseudomonas spp. was observed in both sexes.
In distribution among age groups, results of the study showed that E. coli was more prevalent in old adults (32%) and less prevalent in children and adolescents (18%).A gradual increase in the age groups of young and middle-aged adults has been observed.Similar results were obtained for Klebsiella spp., with the highest prevalence in old adult patients (43%) and the lowest prevalence in children and adolescents (17%).In the case of young and middle-aged adults, the prevalence rates of these isolates were quite similar.
In the case of Enterococcus spp., the results showed the highest prevalence in both young adults (35%) and old adults (35%), followed by moderate (20%) in children and adolescents, and a low prevalence in middle-aged adults (10%).
The highest prevalence of Streptococcus spp. was observed in middle-aged adults and old adults (38%), whereas in young adult patients, the rate was moderate (25%).However, the prevalence rate was not found in children and adolescents.
Surprisingly, Proteus spp.were the most prevalent in children (86%), and no cases accounted for the young and old adult age groups.
On the other hand, Pseudomonas spp.showed the reverse prevalence of Proteus spp.; the highest and the lowest prevalence was highlighted in the old adult age group (83%) and children (17%), respectively.The prevalence of Staphylococcus spp.(25%) was equal across all age groups (Table 1).
A clear picture of multidrug-resistant (MDR) Pseudomonas spp. was found to be resistant to six antimicrobial class agents at the same time, among which multiple were from the same antibiotic class, for example, Cephalosporin.In contrast, only one antibiotic, Colistin, was found to be completely effective, followed by three antibiotics, Ceftazidime, Doripenem, and Piperacillin (83% sensitivity), against Pseudomonas spp.
Interestingly, most antibiotics used in this study, other than Amikacin and Cotrimoxazole, were resistant to Streptococcus spp.
T A B L E 4 Proportion (%) of common urinary pathogens demonstrating sensitivity (S) to antimicrobial agents.(Table 3).Ciprofloxacin, a widely used antibiotic, was found to have a high level of intermediacy (56%) in this study (Table 5).

| DISCUSSION
This study investigated uropathogenic bacteria that cause UTIs, such as E. coli, Klebsiella spp., Enterococcus spp., Streptococcus spp., Proteus spp., Pseudomonas spp., and Staphylococcus spp.E. coli was the most prevalent pathogen, followed by Klebsiella spp.(12.35%) and Enterococcus spp.(8.23%), respectively.The most important finding of this study was that the prevalence of E. coli, Klebsiella spp., and Pseudomonas spp. was very high in the old adult group, and most of this uropathogen showed >90% resistance to 10 commonly used antibiotics.Another important finding was that Proteus spp. was the most prevalent uropathogen in children and adolescents and was predominant in males.Enterococcus spp.showed a higher prevalence in both young and old adults, and Proteus spp. was the most prevalent in children.Staphylococcus spp.showed equal prevalence among all age groups.Multidrug resistance has been observed in some cases, with varying levels of sensitivity to different antibiotic classes.
6][37] It has been reported that it increases by almost 30% in women over the age of 85.9][40][41] The result of the study stating that the prevalence of UTIs in the old adult group was higher than that in other age groups is consistent with these findings.3][44] The main risk factors were ageassociated changes in immune function, the use of urinary catheters, and the presence of comorbidities such as cancer, diabetes, neurological disorders, and stroke.Prior experience with UTIs, nosocomial infections, obstruction of urine flow, high retention of urine compromising renal and kidney defense mechanisms, presence of prostatic hypertrophy in men, loss of estrogen in postmenopausal women, and certain medications, such as anticholinergic drugs. 45,46l of these risk factors make old adults susceptible to UTI.
8][49][50][51][52][53] Overutilization of antibiotics is generally used to prevent the prevalence of UTIs in old adults. 52Consequently, a higher rate of antibiotic-resistant uropathogens was found in patients after taking oral antibiotics. 10,54,55Interestingly, in this study, the highest number of antibiotics were found to be resistant to Pseudomonas spp., which was most prevalent in the old adult population.It is necessary to recommend therapeutic techniques other than antibiotics, such as changes in habit and intake of dietary supplements such as cranberry juice drinks, for UTIs that are prevalent in old adult people. 56evious studies have demonstrated that the prevalence of UTIs in female patients is higher than in male patients worldwide, especially in Africa, Asia, and South Asian countries. 10,57,58Several studies in Bangladesh have reported similar results. 3,6,7,41,59The anatomical structure of women, such as the shorter urethra, being very close to the vagina and anal orifice, hormonal changes during the menopausal period, during sexual intercourse receiving bacteria from their partner, use of contraceptive materials, and involvement in sexual activities using both the vagina and anal orifice, might be the potential reasons for the higher prevalence of UTIs in female patients. 3,60In addition, during pregnancy, numerous hormonal and mechanical changes in the body, glycosuria, aminoaciduria, and urine retention in the bladder contribute to a higher prevalence of UTIs in female patients.Thus, females are more susceptible to UTIs than males, as highlighted in the present study data. 58am-negative bacteria such as E. coli, Klebsiella spp., Proteus spp., and Pseudomonas spp.are causative uropathogens of UTIs. 10,46,61E. coli was found as the major causative agent of UTIs in different studies in Bangladesh, India, and all over the world. 3,5,10,62It has also been found that E. coli is followed by Klebsiella spp. as the cause of UTIs. 5,61The results of this study are consistent with these studies.Our study also reported the involve- showed 100% resistance to Azithromycin and Cefixime, followed by moderate resistance (75%) to Ceftriaxone/Rophin, and Fusidic acid.
These results indicate that all uropathogens, especially Pseudomonas spp.and Enterococcus spp., are multidrug-resistant and affect old adults in the Dhaka South region. 63These findings are similar to those of studies conducted in Bangladesh, India, and other developing countries.Some uropathogens also showed differences in susceptibility to antibiotics compared with previous reports.The place and time may explain these differences.Based on these results it could be suggested that physicians should be careful to select antibiotics for these uropathogens causing UTIs patients.

| CONCLUSION
In this study, multiple drug-resistant (MDR) Enterococcus and Pseudomonas spp.were found to be completely resistant to most antibiotics from the Cephalosporin class and several of the most frequently used antibiotics.The occurrence of MDR Enterococcus spp.infection was higher in females and the prevalence of MDR Pseudomonas spp. was higher in the old adult age group and children than in the young and middle-aged adult age groups.As many commonly used antibiotics are resistant to UTI-causing bacteria, this study may help to identify effective antibiotics to treat specific UTI agents easily, and performing yearly surveillance systems of antibiotic susceptibility patterns can also make it easier.Antibiotic Stewardship Programs may play a significant role in effectively treating bacterial infections and improving clinical outcomes.

T A B L E 5
Proportion (%) of common urinary pathogens exhibiting intermediate (I) response to antimicrobial agents.
The distribution of UTI among gender and age groups of patients.Proportion (%) of common urinary pathogens showing resistance (R) to antimicrobial agents.